Flexible Nanogenerator and Nano-Pressure Sensor Based on Nanofiber Web of PVDF and its Copolymers - Soft Fibrillar Materials: Fabrication and Applications - page 235

(c)

(a)

β γ α α + β + γ

β + γ

β β

(b)

β γ α α + β + γ

β + γ

β β β γ α α + β + γ

β + γ

β β

αα α α α αα α α α α α α α α

v iv

iv

iv

iii

iii

iii

ii

ii

ii

i

i i

1500 1400 1300 1200 1100 1000 900 800 700 600 500 400 1500 1400 1300 1200 1100 1000 900 800 700 600 500 400 1500 1400 1300 1200 1100 1000 900 800 700 600 500 400

Wavenumber (cm − 1 ) Wavenumber (cm − 1 )

Wavenumber (cm − 1 )

1.6 1.6 1.6

(d) (e)

(f)

β -phase
γ -phase
α -phase

1.4

1.4 1.4

1.2 1.2 1.2

1.0 1.0 1.0

0.8

0.8 0.8

β -phase

β -phase
γ -phase
α -phase

0.0 0.0

0.0

γ -phase

α -phase

0.4 0.4 0.4

0.2

0.2 0.2

0.0 0.0

0.0

0 0.01 0.03 0.05

5e-3

PVDF cast film 0 0.25 0.5 0.75 PVDF nano fiber 0 0.01 0.02

MWCNT (wt.-%) in PVDF electrospun nanofiber

CaCl 2 (wt.-%) in PVDF electrospun nanofiber

MWCNT (wt.-%) in PVDF-CaCl 2
(0.5 wt.-%) electrospun nanofiber

Figure 8.6 FTIR-TS of electrospun fibers (a) PVDF-CaCl 2 : (i) PVDF solution-cast film (used for comparison here), (ii) 0, (iii) 0.25, (iv) 0.5,
and (v) 0.75 wt% of CaCl 2 ; (b) PVDF-MWCNT: (i) 0, (ii) 0.01, (iii) 0.03, and (iv) 0.05 wt% of MWCNT; (c) PVDF-CaCl 2 (0.5 wt%) + varying
content of MWCNT: (i) 0, (ii) 0.005, (iii) 0.01, and (iv) 0.02 wt%; relative amount of crystalline phases as a function of additive in PVDF
electrospun samples: (d) with varying CaCl 2 content; (e) with varying MWCNT content; and (f) with CaCl 2 (0.5 wt%) + varying MWCNT
content.